SMTC Corporation Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Debt and Finance Leases - Additional Information (Details)

Debt and Finance Leases - Additional Information (Details)				2 Months Ended	3 Months Ended			6 Months Ended	12 Months Ended
	Sep. 27, 2019 USD ($)	Aug. 08, 2019 USD ($)	Jul. 03, 2019 USD ($)	Jul. 31, 2020 USD ($)	Sep. 27, 2020 USD ($)	Jun. 28, 2020 USD ($)	Mar. 29, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jan. 03, 2021 USD ($) $ / shares	Dec. 29, 2019 USD ($) $ / shares shares	Dec. 30, 2018 USD ($)	Dec. 28, 2020 shares	Sep. 25, 2020 USD ($)	Jun. 26, 2020 USD ($)	Mar. 29, 2019	Mar. 28, 2019	Nov. 08, 2018 shares
Debt Disclosure [Line Items]
Cash restructuring costs	$ 2,300,000
Write-offs of accounts receivable	1,623,000
Write-offs of inventory	1,607,000
Investments under restructuring	$ 2,300,000
Restructuring Charges, Total									$ 4,125,000	$ 7,955,000
Revolving credit facility									34,694,000	34,701,000
Debt Instrument, Unamortized Discount, Total									1,742,000	1,464,000
Amortization of deferred financing fees and debt issuance costs									$ 1,205,000	1,592,000	$ 194,000
Initial term of leases									12 months
Lessee, Operating Lease, Option to Extend Amount									$ 4,518,000
Lessee, Finance Lease, Option to Extend Amount									$ 6,456,000
PNC and TCW Amendment [Member]
Debt Disclosure [Line Items]
Non-recurring labor costs and temporary employee bonuses						$ 1,000,000.0	$ 200,000,000
TCW Fifth Amendment [Member]
Debt Disclosure [Line Items]
Non-recurring labor costs and temporary employee bonuses						$ 1,000,000.0	$ 200,000,000
Increase in aggregate principal amount of indebtedness														$ 3,750,000
Amendment fee														75,000,000
PNC Fourth Amendment [Member]
Debt Disclosure [Line Items]
Increase in aggregate principal amount of indebtedness														3,750,000
Amendment fee														$ 50,000,000
PNC Amendment No. 5 [Member]
Debt Disclosure [Line Items]
Line of credit facility, maximum borrowing capacity													$ 2,000,000
Non-recurring labor costs and temporary employee bonuses					$ 1,500,000
TCW Amendment No. 6 [Member]
Debt Disclosure [Line Items]
Non-recurring labor costs and temporary employee bonuses					$ 1,500,000
PNC Amendment No. 6 [Member] \| Forecast [Member]
Debt Disclosure [Line Items]
Write-offs of accounts receivable, inventory and fixed assets								$ 1,500,000
TCW Amendment No. 7 [Member] \| Forecast [Member]
Debt Disclosure [Line Items]
Restructuring and severance charges, accruals and reserves								1,000,000.0
Restructuring Charges, Total								4,000,000.0
Write-offs of accounts receivable, inventory and fixed assets								1,500,000
Liquidity								7,500,000
Minimum [Member]
Debt Disclosure [Line Items]
Lessee, Operating Lease, Renewal Term									1 year
Maximum [Member]
Debt Disclosure [Line Items]
Lessee, Operating Lease, Renewal Term									5 years
Maximum [Member] \| PNC and TCW Amendment [Member] \| Employees at Zacatecas, Mexico Facility [Member]
Debt Disclosure [Line Items]
Restructuring and severance charges, accruals and reserves				$ 844,000,000
Maximum [Member] \| PNC and TCW Amendment [Member] \| Corporate Selling, General and Administrative Employees [Member]
Debt Disclosure [Line Items]
Restructuring and severance charges, accruals and reserves				156,000,000
Maximum [Member] \| TCW Fifth Amendment [Member] \| Employees at Zacatecas, Mexico Facility [Member]
Debt Disclosure [Line Items]
Restructuring and severance charges, accruals and reserves				844,000,000
Maximum [Member] \| TCW Fifth Amendment [Member] \| Corporate Selling, General and Administrative Employees [Member]
Debt Disclosure [Line Items]
Restructuring and severance charges, accruals and reserves				156,000,000
Maximum [Member] \| PNC Amendment No. 6 [Member] \| Forecast [Member]
Debt Disclosure [Line Items]
Restructuring Charges, Total								$ 4,000,000.0
Maximum [Member] \| PNC Amendment No. 6 [Member] \| Employees at Zacatecas, Mexico Facility [Member]
Debt Disclosure [Line Items]
Restructuring and severance charges, accruals and reserves				$ 1,000,000.0
PNC Bank [Member]
Debt Disclosure [Line Items]
Maturity date									Nov. 08, 2023
PNC Bank [Member] \| Base Rate [Member] \| Minimum [Member] \| Term Loan [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate									0.75%
PNC Bank [Member] \| Base Rate [Member] \| Maximum [Member] \| Term Loan [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate									1.25%
PNC Bank [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Term Loan [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate									2.50%
PNC Bank [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Term Loan [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate									3.00%
PNC Bank [Member] \| Foreign Line of Credit [Member]
Debt Disclosure [Line Items]
Maturity date									Nov. 08, 2023
Line of credit facility, maximum borrowing capacity		$ 15,000,000
Line of credit facility, maximum borrowing capacity, increased		$ 20,000,000
PNC Bank [Member] \| Foreign Line of Credit [Member] \| Base Rate [Member] \| Minimum [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate		0.75%							0.75%
PNC Bank [Member] \| Foreign Line of Credit [Member] \| Base Rate [Member] \| Maximum [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate		1.25%							1.25%
PNC Bank [Member] \| Foreign Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate		2.50%							2.50%
PNC Bank [Member] \| Foreign Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate		3.00%							3.00%
PNC Bank [Member] \| Revolving Credit Facility [Member]
Debt Disclosure [Line Items]
Line of credit facility, maximum borrowing capacity		$ 65,000,000							$ 65,000,000
Revolving credit facility									34,694,000	34,701,000
Line of Credit Facility, Remaining Borrowing Capacity									$ 28,447,000	$ 21,644,000
TCW Asset Management Company, LLC [Member]
Debt Disclosure [Line Items]
Maturity date									Nov. 08, 2023
Class of Warrant or Right, Outstanding (in shares) \| shares												651,949					504,735
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares										511,949
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares									$ 0.01
Class of warrant or right term									84 months
Warrants and Rights Outstanding									$ 3,233,000	$ 1,730,000	$ 1,898,000
Share Price (in dollars per share) \| $ / shares									$ 4.96	$ 3.38
TCW Asset Management Company, LLC [Member] \| Rights Offering and the Registered Direct Offering in June 2019 [Member]
Debt Disclosure [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares										7,214
TCW Asset Management Company, LLC [Member] \| Warrants Issued During Fourth Quarter of 2020
Debt Disclosure [Line Items]
Debt Instrument, Unamortized Discount, Total									$ 651,000
Warrants and Rights Outstanding									$ 140,000,000
Share Price (in dollars per share) \| $ / shares									$ 4.65
TCW Asset Management Company, LLC [Member] \| Term Loan [Member]
Debt Disclosure [Line Items]
Additional prepayment fee after closing date, percent, first twelve months									3.00%
Additional prepayment fee after closing date, percent, year two									2.00%
Additional prepayment fee after closing date, percent, year three									1.00%
TCW Asset Management Company, LLC [Member] \| Term Loan A [Member]
Debt Disclosure [Line Items]
Maturity date									Nov. 08, 2023
Debt instrument, leverage ratio required															3.75	3.50
Repayments of debt		10,000,000
Maximum paydown of debt instrument, permit		$ 10,000,000
TCW Asset Management Company, LLC [Member] \| Term Loan B [Member]
Debt Disclosure [Line Items]
Maturity date									Jul. 03, 2019
Repayments of debt			$ 12,022,000
TCW Asset Management Company, LLC [Member] \| TCW Amendment No. 7 [Member]
Debt Disclosure [Line Items]
Class of Warrant or Right, Outstanding (in shares) \| shares												140,000
TCW Asset Management Company, LLC [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Financing Agreement Through June 30, 2020 [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate		8.75%							8.75%
TCW Asset Management Company, LLC [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Financing Agreement Through June 30, 2020 [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate		7.25%
TCW Asset Management Company, LLC [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Term Loan A [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate									7.25%
TCW Asset Management Company, LLC [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Financing Agreement Through June 30, 2020 [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate		8.75%
TCW Asset Management Company, LLC [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Term Loan A [Member]
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate									8.75%
TCW Asset Management Company, LLC [Member] \| Term Loan A [Member]
Debt Disclosure [Line Items]
Repayments of debt		$ 10,000,000
Revolving credit facility									$ 37,188,000	$ 38,750,000
Line of Credit Facility, Remaining Borrowing Capacity									2,016,000	2,286,000
Debt Instrument, Unamortized Discount, Total									1,742,000	$ 1,464,000
Amortization of deferred financing fees and debt issuance costs									$ 1,562,000